Your car’s cooling system works hard to keep the engine from overheating. Coolant gradually loses its efficiency when it becomes contaminated with dirt, corrosion, and debris. A coolant flush ensures that your engine operates smoothly by replacing old coolant with new fluid.
This guide includes instructions to change coolant, as well as radiator flush methods, and coolant leak identification steps. Motorists need regular cooling system flushes because they keep engines running properly while saving money on expensive radiator repairs.
Why Is A Coolant Flush Important?

The cooling fluid protects the engine from heat damage while stopping rust formation while aiding in freezing and overheating defense. The aging process of coolant makes it acidic thus causing damage to engine parts. These symptoms indicate the need for radiator service:
Your engine often heats up excessively when the temperature gauge rises repeatedly because water keeps escaping or there are blockages throughout the cooling system.
- Coolant leaking from bottom of car shows either a failing radiator or faulty hoses.
- If your radiator housing shows brown or murky discoloration in your cooling system the fluid requires immediate flushing out.
- The heat core leak leads to coolant fume detection inside your vehicle’s interior.
Regular logbook car servicing help preserve coolant amounts, which protects against system harm.
How to Change My Coolant: Step-by-Step Guide?
Before starting, ensure your engine is completely cool to avoid burns. You’ll need some basic tools and safety gear for this general car repair.
Tools and Items You’ll Need
- Gloves & Safety Glasses – Coolant is toxic, so protection is essential.
- Coolant Flush Cleaner – Removes debris from the radiator.
- Drain Pan – To collect old coolant.
- New Coolant – Check your manual for the recommended type.
- Funnel – Makes filling easier.
- Empty Container – To store drained coolant for proper disposal.
- Wrenches & Pliers – For removing drain plugs or hoses.
- Thread Sealant – If your car has a block drain plug.
Step 1: Prepare your vehicle.
- Park the car on a flat surface and apply the handbrake.
- Shift into park (automatic) or first gear (manual).
- Set the heater to maximum to allow coolant to flow through the heater core.
- Locate the coolant pressure cap (either on the radiator or in a separate tank).
- Wait for the engine to totally cool before removing the cap.
Step 2: Drain the old coolant.
- Find the radiator drain plug under your automobile. If your car does not have a plug, remove the bottom radiator hose to drain the coolant.
- Before you loosen the plug, place a drain pan underneath it.
- Let the coolant drain fully.
- Replace the drain plug and tightly reattach the radiator hose.
Tip: If coolant spills from the car’s bottom after tightening the plug, check for loose fittings.
Step 3: Perform a cooling system flush.
- Place a coolant filling funnel in the radiator.
- Pour in the radiator flush cleaner and top it over with water.
- Start the engine and let it run for 10–30 minutes to circulate the flush.
- Once finished, switch off the engine and allow it to cool completely.
Step 4: Drain the Flushing Fluid.
- To remove the flushing fluid, repeat Step 2.
- If the drained liquid remains highly unclean, repeat the cooling system flush procedure.
Step 5: Remove the remaining coolant from the system.
- Use a suction gun to drain any remaining coolant from the reservoir.
- Check to see if your car has a blocked drain plug (according to the service manual).
- If it is extant, remove it to drain any residual liquids.
- Before tightening the block drain plug back in place, apply thread sealant.
Step 6: Add new coolant.
- Use a funnel to slowly pour new coolant into the radiator or coolant reservoir.
- Check your manual for the appropriate coolant type and amount.
- If the radiator fills up before the necessary level, air becomes trapped in the system.
Step 7: Bleed the cooling system.
- Squeeze the top radiator hose to release some air bubbles.
- Start the engine and allow it to achieve operating temperature.
- Keep a watch on the funnel, as air bubbles escape.
- Continue to add coolant as needed until the bubbles stop.
- Turn off the engine and tighten the radiator cap.
- Fill up the coolant reservoir to the appropriate level.
- Check your service handbook to see whether your vehicle has bleed valves to expel air more quickly.
How to Dispose of Old Coolant?

Coolant is toxic, so never pour it down the drain. In Australia, take the used coolant to:
- Local council recycling facilities
- Mechanics in Perth or other car workshops
- Authorized waste disposal centers
Check local regulations for proper disposal methods.
Final Thoughts
Performing a coolant flush remains crucial because it protects engine health and stops overheating as well as corrosion damage. The cooling ability of coolant deteriorates with time, which causes problems in the cooling system as well as needing radiator maintenance. Periodic radiator flushes together with coolant inspections prevent unaffordable vehicle breakdowns.
Pay attention to the lower vehicle side for coolant leakage or abnormal temperature changes because emergency action becomes necessary. A mechanic or a car workshop professional performs the most thorough cooling system flush in Perth.
Engine performance and unexpected failure risk both decrease due to proper maintenance of your cooling system. Car performance depends on productively changing coolant either through your own maintenance or a professional service.
Need a professional? Visit us – a trusted car workshop in Perth for expert help!
FAQs
Q.1 How much does a coolant flush cost in Australia?
Answer:1
The cost of a radiator flush fluctuates by location and kind of vehicle. Generally, a professional radiator service will set you back about $100–$250. If you do it yourself, the estimated cost ranges anywhere from $30–$70, depending on the brand of coolant you choose and what tools you already have
Q. 2 Can you put new coolant over old coolant?
Answer:2
No. Mixing old and new coolant will diminish the effectiveness, and could create sediment and corrosive contaminants. Regardless of the situation, you should always drain all the old coolant before adding new fluid.
Q.3 How often should I change my car coolant?
Answer:3
It depends on your car model and coolant type:
- Older cars: Every 2–5 years or 50,000–100,000 km
- Modern cars with long-life coolant: Every 160,000 km
- Check your vehicle manual for exact recommendations.
Q. 4 Is it okay to mix coolant with water?
Answer:4
It depends. Some coolants come pre-mixed (ready to use), while others require dilution. If your coolant requires mixing, use distilled water—not tap water, as minerals can cause deposits in the system.
Q. 5 Does it matter what color coolant I use?
Answer: 5
Yes! Different coolant colors indicate different chemical formulations. Using the wrong coolant type can cause corrosion or cooling system damage. Always use the coolant specified in your car’s service manual.
Q. 6 How to check coolant level?
Answer: 6
- Ensure your engine is cold before opening the coolant reservoir.
- Locate the coolant tank (usually a transparent plastic container).
- Check the MIN and MAX level markings.
- If below MIN, top it up with the correct coolant.